Introduction
Neurological is an emerging cross discipline in modern linguistics, integrating speech, neuroscience, psychology and cognitive science, specializing in language acquisition, Physiological mechanisms and psychological mechanisms of generating and understanding, study how the brain produce, receives, stores and extracts information, thus exploring the relationship between brain and language, fully reflecting the development trend of integrated integration of various disciplines of contemporary science, is the frontier of contemporary academic research And a broad development prospect.
History origin
Human has already noticed the relationship between brain and language very early. The ancient Egyptians have recorded illness due to brain damage, which is also the modern default. However, the study of truly scientific significance is from the post-halving of the 19th century. In 1861, the French doctor P. Broca (1824 ~ 1880) found a special area of the cerebral cortex (rear behind the left hemispheric) related to the generation of words, the injury of the region caused the patient's pronunciation and declaration, or though It can be said, but it is not possible to constitute a discourse representative. In 1874, German physiologist C. Vernick (1848 ~ 1905) found that another region of the cerebral skin (behind the left hemispherical lobe) controls the reception and understanding of speech, this area damaged patients unable to understand others If you say, even you can't distinguish between voice. The above two cortical layers were later named Boros and Vernk District, respectively.
Since then, the study of neurological mechanisms in the language has achieved certain achievements. Modern anatomy and physiology have accumulated a lot of knowledge about human brain structure, but how the live human brain acts, is still a mystery. Difficulties are, people can't open the live people to study directly.
Application method
The method of modern neurological language is widely used: First, the pathological method is observed to observe the influence of brain injury on language function; the second is electronic physiology The method, that is, through bioelectric testing to observe the activities of the brain in the speech process. The results of the study showed that adults' speech hub is located only on one side of the cerebral cortex, which is called "single-sided" or "hemisphere advantage". Which hemisphere is located in the speech center, with the idle left hand or the right hand, there is a certain cross connection: almost all the people mainly use the right hand, its speech center is located in the brain left hemisphere; 60 ~ 70% in the left hand, 60 ~ 70% is also the left half ball Advantages, the rest of the people are the advantage of the right hemisphere. There is also a certain cross-container between the hearing organ and the brain, the language advantage of the left hemisphere leads to the hearing advantage of the right ear. Two different speakers are simultaneously released on both ends of a person, first perceive and remember, usually the voice of the right ear. This is because the voice of the right ear can be sent directly to the left hemisphere to make a language "decoding", and the speech sound heard by the left ear is first transferred to the left hemisphere by the right hemisphere (Fig. 2). Left ear is biased to perceive non-linguistic sounds, such as noise in the environment, the sound of people, the sound of music, etc. Anatomists have found that the fetus's big brain right hemisphere is slightly smaller than the left hemisphere; the lupid auditory experiment also proves that the brain hemispheries of the newborn have a strong bioelectric reaction to speech stimulation. The formation of the left hemisphere language, it seems to be related to genetic factors. However, environmental factors and time factors also play an important role in the directional division of the brain two half balls. The language advantage of the left hemisphere of the child is to establish a gradual establishment in the process of learning the language. The big brain and right hemispheres of the newborn baby have also form a physiological basis for forming language functions, but because of the only one hand, the language ability of the right hemisphere is suppressed.
Indening symptoms
The study of deflation can be a series of issues such as clarifying the formation of speech center, the division of labor of the brain, and the positioning of language functions. Since most people's speech center is located in the left hemisphere, speech barriers are typically caused by damage to the left hemisphere. The possibility of influential cure is largely dependent on the age of the patient. Generally speaking, children under 4 years old, if the left hemisphere is damaged, the right hemisphere can also develop language skills more smoothly. However, if the 4 years old or more children suffer from influence, their language skills will be returned to the 4-year-old level, and it takes a while to have the original language skills. This shows that at a minor stage, the child's brain right hemisphere still has the possibility of replacing the left hemisphere to form a speech center. However, some scholars pointed out that the words of the speech have been transferred to the right hemisphere, and there is no difficulty in learning vocabulary, but the ability of the joint phrase will be affected. If the damage of the left hemisphere occurs after the adolescence, it will make people completely lose the language function, because the adult's right hemisphere has passed the development of language function.
Dispute Differences
About the singularity of the speech center and the language advantage of adult left hemispheres, experts have achieved more consistent views. However, for the specific language function, it is still controversial to the special area of the cerebral cortex.
Positioning Theory
Long-term popular "positioning theory" believes that specific brain cortex controls specific language functions, a brain disorder causes a certain The loss of language functions associated with it, such as the injury in the Brooka area and Wilnik district, affect the expression of language and auditory cognitive functions, respectively. Modern scholars also believe that voice, syntax, vocabulary and semantics have corresponding special neural mechanisms.
Overall theory
However, pure cases do not exist, a more prominent symptom is always accompanied by another slight symptom, this fact makes some scholars to "position "Theory" has doubt, proposes "overall theory": There is a close relationship between the parties of the human brain, so language functions are unified, and the damage of any part of the human brain may affect the functions of language. It is pointed out that all patients with aphasia lack a basic language ability - the ability to make propies with symbols.
The above two perspectives are not, there is no conclusion. However, narrow positioning theory or extreme overall theory is unfavorable to further research.